I had a .btinternet email account for many years (so old the address was my name) that started to be engulfed with spam four or five years ago. I subsequently read that Yahoo, who were the email service provider for BT at that time, were hacked and tens of millions of email address, were stolen. There have been many major hacks of online databases including one at Currys who had my email address, and those are just the ones that we know about. Then my account started playing up continually, locking me out and requiring me to change my password. I suspect someone was trying to get into the account, trying passwords they had phished from stolen databases.
Anyway, I got fed up with that, and wading through hundreds of spam emails looking for the odd genuine one that had got caught up in them, and got myself a gmail email account. It was a niusance changing my details at my bank, amazon, ebay, paypal, et al., and also getting all my contacts to update their address books, but it was worth it; I check my gmail spam filter occasionally and invariably there is nothing in it at all.